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 Question from Lucy: Find the area of the the figure described: a semicircle with arc length 3 pi.

Hi Lucy,

What is the formula for the circumference of a circle of radius $r?$ Half of that is the length of the semicircular arc which you know is $3 \pi.$ Solve for $r.$ Now you know the radius of the circle, what is its area? What is the area of the semicircle?

Penny

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